Grid for conveyer belt systems



Dec. 24, 1940.

F.. PARKER GRID FOR GONVEYER BELT SYSTEMS Filed July 19, 1939 4 Sheets-Sheet 1 I'm? Parker;

INVENTOR ATTORNEYS Dec. 24, 1940,

F. PARKER GRID FOR CONVEYER BELT SYSTEMS Filed July 19. 1959 4 Sheets-Sheet 2 Q BY ATTORNEYS rker;

4 Sheets-Sheet 5 Dec. 24, 1940. F. PARKER- GRID FOR CONVEYER BELT SYSTEMS Filed July 19, 1939 Dec. 24, 1940. F.' PARKER I GRID FOR CONVEYER BELT SYSTEMS 7 4 Sheets-Sheet 4 Filed July 19, 1959 V 072% Parke w INVENTOR ATTORNEYS Patented Dec. 24, 1940 UNITED STATES PATENT? OFFICE GRID FOR CONVEYER BELT SYSTEMS Frank Parker, Edmonds, Wash,

Application July 19, 1939, Serial No. 285,453

2 Claims.

The invention relates to'a screening apparatus and more especially to a cleaning grid for conveyer belt systems.

' The primary object of the invention is the provision of a grid of this character wherein the same is disposed over a conveyer belt adapted for moving material such as loose dirt and thus dirt can-be loaded onto the belt with rocks of larger sizes removed from the dirt in its delivery onto the belt, thereby enabling the proper handling of I the dirt for the conveying of the same to a point for distribution or deposit.

Another object of the invention is the provision of a grid of this character wherein the rock removed from the dirt as the latter is loaded upon a conveyer belt will be caused to gravitate into chutes-at opposite sides of the grid whence such rock can be delivered onto trucks for disposition thereof. 7 v

A further object of the invention is the provi sion of a grid of this character wherein the same is novel in its entirety and assures the requisite screening of material such as loose dirt to remove heavy solid particles as for example rocks, of determined sizes to rid these from the load upon the belt thereby enabling the convenient handling of the load and the rock will be cleaned from the grid should the same become lodged therein and in this manner eliminating the clogging of such grid in the use of the same.

A further object of the invention'is the provision of a grid of this character wherein it is made up of a plurality of sections, these being selectively cleaned to avoid clogging thereof in the use of the same. I

Astill further object of the invention is the provision of a grid of this character wherein dirt when loaded into trucks can be conveniently dumped onto the grid for the cleaning of the dirt during the deposit thereof onto a conveyer belt and in this manner the entire grid can be maintained clean for screening operations.

A still further object of the invention is the provision of a grid of this character which is comparatively simple in construction, thoroughly reliable and efficient in operation, susceptible of being cleaned with dispatch and inexpensive to manufacture and install.

With these and other objects in view, the invention consists in the features of construction, combination and arrangement of parts as will be hereinafter more fully described in detail, illustrated in the accompanying drawings, which disclose the preferred embodiment of the invention and pointed out in the claims hereunto appended.

In the accompanying drawings:

Figure l is' an elevation partly in section of a grid and adjuncts constructed in accordance with the invention.

Figure 2 is a sectional view taken on'the line 22 of Figure 1 looking in the direction of the arrows.

Figure 3 is a sectional View taken on the line 3--3 of Figure 1 looking in the direction of the arrows.

Figure 4 is a perspectiveview of the driving and" control mechanism for the grid and shown in association with an electric circuit and power motor operated by current supplied therefrom, the circuit being diagrammatically illustrated.

Figure 5 is a fragmentary vertical transverse sectional. view showing in detail the ratchet latching mechanism employed with the grid.

Similar reference characters indicate corresponding parts throughout the several views in the drawings.

Referring to the drawings in detail, A designates generallya conveyer belt horizontally arranged and driven in any suitable manner for conveying loose material from a receiving point to a delivery point. Above this conveyer belt A is a substantially hopper-shaped feeder trough I0, being permanently built in its superposed relation to said belt in a stand ll. overhanging this trough l and built within the stand H is a grid constituting the present invention and hereinafter fully described.

The grid involving the invention comprises end pieces or plates l2 and I3 respectively and intermediate pieces or plates I4. These plates l2, l3 and 14 are perpendicularly arranged and built within the stand II for permanency, being peaked and having fitted therewith a central ridge piece IS. The end and intermediate pieces I2, [3 and I4 are spaced apart, yet the said pieces M are in contiguous relation to each other for providing a gap I6 therebetween. The ridge piece l which is a partialcrown for the grid extends longitudinally centered with respect to the pieces l2, l3 and I4.

Between the pieces l2-l4 and l3-I4 respectively, are grouped grid bars I! which are arranged in upward convergent relation to each other at opposite sides of the ridge piece l5 and are movably held within the stand II for the screening of loose material, such as dirt dumped thereonto from trucks or other load carriers, not shown, these being adapted to be driven onto platforms l8 for dumping purposes.

The grid is for the purpose of removing rocks from the loose material, that is to say, dirt when dumped thereon from the trucks or carriers upon the platforms I8. These platforms I8 are at opposite sides of the ridge piece I 5. The platforms I8 are permanently built on the stand II which with the grid constitutes a bunker. The loose dirt screened between the bars I1 gravitates into the hopper-like trough I0 and thence therefrom onto the conveyer belt A for the loading of the same and the carrying of this load to a point of distribution or deposit.

At opposite sides of the stand I I below the grid bars I1 with relation to the lowermost ends thereof are inclined chutes I9 which are receptive to rocks or other solid matter removed from the loose dirt by the grid in that these particles, such as rocks or the like will gravitate from the grid into the said chutes whence the same will be loaded into a truck or other eonveyer on discharge from the chutes I9.

Arranged below the grid bars I1 are stationary grid combing or cleaning units, each including a series of spaced bars 20 fixedly held in their spaced parallel relation to each other by inner and outer longitudinally disposed angle rails 2|, these being joined to the bars 20 which through such arrangement are adapted to have enter therebetween the grid bars I1 for clearing solid matter, rocks or the like when clogging the spaces between said grid bars. The bars I1 in series are adjusted in a manner presently described for grid cleaning operation. The units having the bars 20 are arranged in corresponding sloping relation to the grid bars I1 but are disposed beneath the same.

Carried by the pieces I2, I3 and M in underlying close relation to the grid bars I1 are inner and outer guide pulleys 22 and 23 respectively over which are trained lift cables 24, these having branches 25 and 26 respectively which are terminally connected to eye members 21 on swinging cranks 28 connected by pivot shafts 29 to the rails 2| and to rocking shafts 30. The swinging cranks are associated with the shafts 30' and on the swinging of said cranks the units having the bars I1 will move toward or away from the bars 20 and in these movements remove clogged or wedged material in the grid so that the latter will be clean for screening of loose dirt.

Arranged longitudinally and centrally of the stand I I are spaced parallel power shafts 3| and 32 respectively, the pieces I2, I3 and I4 being provided with clearances for the said power 55 shafts which pass therethrough. These power shafts are journaled in bearings 33 suitably supported in the stand II. Splined on the power shafts 3| and 32 are shiftable clutch members 34 for turning with the said shaft and engage- 60 able with or disengageable from these clutch having the bars Zll, those of the pairs being armembers are companion clutch members 35, being loose upon the shafts 3| and 32 respectively. These clutch members 35 have cable spools 36 arranged in pairs for the respective combing units ranged at opposite ends of such units and operate the cables 24 which are adapted to be wound on and unwound from said spools in the working of the grid. On the winding of the cables 24 on these spools 36 the series of bars I1 are moved with relation to the bars 20.

The clutch members 34 of the pairs associated with the spools 36 are thrown toclutching and declutching positions through the use of throw 75 rods 31 pivoted at 38 and 39 respectively and also pivoted at 40 to throw levers 4|, these being conveniently located to a platform 42 in the stand II for an operator of the machine, being hand manipulated. The levers 4| have connected thereto coil springs 43 which normally hold the members 34 in declutching positions. When the members 34 are in clutching position with the companion members 35 the spools 36 are rotated.

The shafts 3| and 32 are seated with meshing driven gears 44 for the operation thereof in unison with each other and rotate reversely one with the other, While the shaft 3| has fitted thereto a worm screw pinion 45 meshing with a worm feed gear 46 operated from the power shaft of a power motor 41. in the stand I I and is in an electric circuit having the current wires 48 and 49 respectively. This circuit has arranged therein a push button switch 50, a magnetic switch 5| and a cam operated switch 52 respectively, the electromagnet of this magnetic switch 5| being indicated at 53 and is arranged parallel with the circuit. The cam actuated switch 52 has its operating cam 54 fixed to the power shaft 3| so that when the said power shaft has completed a single cycle of rotation the switch 52 operates to open the circuit to the motor 41 for the stopping thereof while a hand push button switch functions as a starting switch for the said motor 41. The rotation of the shafts 3| and 32 operate the units having the bars I1 so that the cleaning of the grid will be accomplished. A selected unit having the bars I1 is brought into operation by actuating the lever 4| for the clutching of the clutch member 34 with the companion clutch member 36, being required that the said lever 4| be held in a thrown position to maintain clutching engagement of these members 34 and 35 with each other. On the release of this lever 4| the spring 43 attached thereto becomes active for the declutching of the members 34 and 35.

Each member 35 is formed with a ratchet gear 55 with which coacts a ratchet pawl or dog 56 fixed to a rocking shaft 51. In association with this pawl or dog 56 is a coiled tensioning spring 58 which functions to normally hold the pawl or dog in engagement with the ratchet gear 55 and thereby locking the member 35 against rotation in one direction by allowing it to rotate in a reverse direction so that when a unit having the bars I1 has been moved it will be latched until the pawl or dog 56 is released from the gear 55. The shaft 51 having the pawl or dog fixed thereto carries a foot treadle 59 so that on depressing The motor is suitably supported the latter the pawl or dog 56 can be released from the gear 55 whereupon the unit having the bars I1 will gravitate to a lowered position due to the inherent weight thereof.

It is desirable to have the power motor 41 equipped with a brake mechanism, not shown, to prevent coasting thereof on the opening of the circuit to this motor.

The treadles 59 are located contiguous to the platform 42 for manual operation thereof and these treadles in a group enable selected control of the unit having the bars I1. The motor 41 on the starting thereof is active until the circuit thereto is opened by the cam switch 52 which controls the opening and closing of the said switch on the rotation of the shaft 3| as will be apparent from Figure 4 of the drawings.

What is claimed is:

1. The combination of a stand having a discharge hopper, mechanically raised and gravity lowered movable grid bars arranged in spaced parallel relation to each other above said hopper, groups of spaced parallel stationary cleaner rails cooperating with the grid bars, mechanism movably suspending the groups of movable grid bars whereby the latter will approach and recede from said cleaner rails, platforms overhanging portions of said grid bars for dumping trucks in discharging loose material onto said bars, chutes at opposite sides with respect to the hopper and accommodating material gravitated from said grid bars, mechanism having connection with the groups of movable grid bars for selectively moving the same, power means associated with said mechanism, electrical equipment controlling the operation of said power means, and manually controlled ratchet gear and pawl connections associated with the groups of grid bars for effecting the mechanical raising of the latter and the releasing of such bars for gravity lowering of the same.

2. The combination of a discharge hopper, groups of normally stationary grid bars disposed over said hopper, groups of spaced parallel stationary cleaner rails positioned below said groups of grid bars, each cleaner rail being vertically aligned with the space between two adjacent grid bars, means operable at the will of an operator for independently lowering said groups of grid bars to the level of said cleaner rails, means for raising said grid bars to their normal raised position, and means for maintaining said bars stationary in their normal raised position.

' FRANK PARKER. 

